[v3] Prepare for v3

.github/dependabot.yml

@@ -0,0 +1,9 @@
+version: 2
+
+updates:
+
+  # Keep dependencies for GitHub Actions up-to-date
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'daily'

.github/workflows/configlet.yml

@@ -0,0 +1,16 @@
+name: Configlet CI
+
+on: [push, pull_request, workflow_dispatch]
+
+jobs:
+  configlet:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+
+    - name: Fetch configlet
+      uses: exercism/github-actions/configlet-ci@main
+
+    - name: Configlet Linter
+      run: configlet lint

bin/fetch-configlet

@@ -1,34 +1,58 @@
-#!/bin/bash
-
-LATEST=https://github.com/exercism/configlet/releases/latest
-
-OS=$(
-case $(uname) in
-    (Darwin*)
-        echo "mac";;
-    (Linux*)
-        echo "linux";;
-    (Windows*)
-        echo "windows";;
-    (*)
-        echo "linux";;
-esac)
-
-ARCH=$(
-case $(uname -m) in
-    (*64*)
-        echo 64bit;;
-    (*686*)
-        echo 32bit;;
-    (*386*)
-        echo 32bit;;
-    (*)
-        echo 64bit;;
-esac)
-
-VERSION="$(curl --head --silent $LATEST | perl -nE 's/\R//g; /^location:/i && print [split/\//]->[-1]')"
-URL="https://github.com/exercism/configlet/releases/download/$VERSION/configlet-$OS-${ARCH}.tgz"
-echo "VERSION = $VERSION"
-echo "URL = $URL"
-
-curl -s --location $URL | tar xz -C bin/
+#!/usr/bin/env bash
+
+set -eo pipefail
+
+readonly LATEST='https://api.github.com/repos/exercism/configlet/releases/latest'
+
+case "$(uname)" in
+  Darwin*)   os='mac'     ;;
+  Linux*)    os='linux'   ;;
+  Windows*)  os='windows' ;;
+  MINGW*)    os='windows' ;;
+  MSYS_NT-*) os='windows' ;;
+  *)         os='linux'   ;;
+esac
+
+case "${os}" in
+  windows*) ext='zip' ;;
+  *)        ext='tgz' ;;
+esac
+
+case "$(uname -m)" in
+  *64*)  arch='64bit' ;;
+  *686*) arch='32bit' ;;
+  *386*) arch='32bit' ;;
+  *)     arch='64bit' ;;
+esac
+
+curlopts=(
+  --silent
+  --show-error
+  --fail
+  --location
+  --retry 3
+)
+
+if [[ -n "${GITHUB_TOKEN}" ]]; then
+  curlopts+=(--header "authorization: Bearer ${GITHUB_TOKEN}")
+fi
+
+suffix="${os}-${arch}.${ext}"
+
+get_download_url() {
+  curl "${curlopts[@]}" --header 'Accept: application/vnd.github.v3+json' "${LATEST}" |
+    grep "\"browser_download_url\": \".*/download/.*/configlet.*${suffix}\"$" |
+    cut -d'"' -f4
+}
+
+download_url="$(get_download_url)"
+output_dir="bin"
+output_path="${output_dir}/latest-configlet.${ext}"
+curl "${curlopts[@]}" --output "${output_path}" "${download_url}"
+
+case "${ext}" in
+  *zip) unzip "${output_path}" -d "${output_dir}"   ;;
+  *)    tar xzf "${output_path}" -C "${output_dir}" ;;
+esac
+
+rm -f "${output_path}"